Safety Performance Study of Shared Pedestrian and Vehicle Space in New Zealand

Road users in a shared space are expected to travel at low operating speeds or very near walking speeds. This expectation is to ensure that an urban street functions as a destination and that the dominance of the vehicular traffic is neutralized. The implementation of a shared space concept on a public road requires a safety evaluation, especially for vulnerable road users such as pedestrians and cyclists. However, the evaluation is difficult because of potential traffic conflicts across the whole road corridor (public right-of-way) except for the designated areas that are free of vehicles. This study explored the results of a safety analysis of a shared zone in Auckland, New Zealand. Along with the recorded crash history, the before (2010) and after (2011 and 2012) data were systematically collected with video surveys and traffic counters. The vehicle speeds, volumes, and road user interactions were processed and analyzed. The outcome of the vehicle speed study highlighted the need for traffic calming to be incorporated into the shared space design to restrain vehicle operating speed, especially for off-peak periods. Further, this study challenged the traditional notion and application of the continuum of traffic events in which potential conflicts (termed interactions in this study) and uninterrupted passages were the foundation of the number of injury or fatal crashes, specifically in a shared pedestrian and vehicle space environment.